Mobile menu navigation items are inaccessible at full-page zoom

[shyusu4]

Issue

When zooming in 200% or more on the website, some navigation items in the mobile menu become inaccessible.

Steps to reproduce
Arrive on the site at 200% zoom or more and open the menu toggle.

Suggested fix
Adjust scrolling styles on .header__nav--mobile.is-visible to make sure the whole height of the element’s children is reachable via scrolling.

Reference
Wagtail.org | Accessibility audit spreadsheet

[AdityaSharma-Git3207]

I believe this may be addressed by the mobile menu scrolling changes proposed in #582 , which improve scrolling behaviour for constrained viewport heights.

That PR is currently pending review. Once it’s merged, it may be worth re-checking this issue at 200–300% zoom to confirm whether all menu items are reachable.